Your Name
2016-01-24 02:26:47 UTC
In one topic recently the idea of realistic space sequences in sci-fi
shows / movies came up (e.g. Babblealong 5 vs Star Wars). By
coincidence this article was in yesterday's New Zealand herald
newspaper (23 January, 2016) ...
Be prepared to suspend scientific belief
when you go to the movies
----------------------------------------
It's a month since the release of Star Wars: The Force
Awakens, and for pedants there's much to find wrong with
the Star Wars movies. Laser beams moving slower than
300,000km a second, and that sort of thing.
To be honest, I can live with those inaccuracies. Star
Wars is a fantasy with spaceships instead of dragons,
and isn't supposed to be as scientifically accurate as,
say, The Martian or 2001: A Space Odyssey.
But could more science be slipped into science fiction,
including the Star Wars movies, without spoiling the
fun? Let's go off-world and see if it could happen.
Dogfights in outer space
A staple of science fiction is combat between spacecraft
flying through outer space. Unsurprisingly, these fights
of fancy are often reminiscent of combat on Earth.
In Star Wars, the spacecraft fly around like fighter
planes, with engines pushing them along the direction of
travel and with speeds that appear to be hundreds of
kilometres an hour.
But spacecraft orbiting just above our atmosphere travel
at almost 8km every single second (about 28,800km/h).
And because of the vacuum of space, they can orient
themselves arbitrarily.
If you want to slow your spaceship, just turn around,
"fly backwards" and fire your engines.
What would combat between two orbiting spacecraft be
like? Well, head-on two spaceships would approach each
other at almost 16km a second! Fast, but not exactly
cinematic.
If the combatants wanted to execute turns (and had
unlimited fuel), they would fire rockets at 90 degrees
to the direction of travel. It would be circle work in
outer space.
Executing a 180-degree turn would take some time at
these speeds. Even if you executed a crushing 10G turn,
it would take four minutes to turn around. Time enough
for a snack and some social media updates. Perhaps that
explains why movie directors prefer speeds and
manoeuvres barking back to the Battle of Britain.
Under pressure
The 1979 movie Alien (with Sigourney Weaver) was
famously advertised with the tagline "in space no one
can hear you scream.
Audible sound waves cannot travel through a vacuum, and
yet many science fiction movies feature sound effects in
the vacuum of space. This is particularly true for the
more fantastical movies, such as Star Wars and Star
Trek, whereas the more realistic ones tend to avoid this.
One thing that science fiction gets partially right is
explosive decompression. Atmosperic pressure is
101 kiloPascals or 14.7 pounds per square inch. Blow
open the hatch to your spacecraft and you'll briefly
have a big force pushing you out the door. But the power
of such forces is often grossly exaggerated.
In The Martian movie (spoiler alert), astronaut Mark
Watney is propelled with vast force from air leaking out
of a small hole in his space suit. If this was the way
air pressure worked, slicing your bike tyre open would
launch you metres into the air.
Fortunately, that doesn't happen.
If a kilogram of air was expelled from an astronaut's
space suit at 200km/h, an astronaut with a mass of 200kg
(that's including the space suit) would be accelerated
to just 1km/h.
Mark Watney wouldn't "get to fly around like Iron Man",
as he said in the movie, but would move closer to a
snail's pace.
Perhaps it is understandable that this is one of the
relatively few areas where The Martian sacrifices
scientific accuracy for drama.
Technobabble
It isn't hard to find errors in the technical dialogue
of science fiction movies. After the release of Star
Wars: The Force Awakens, American astrophysicist Neil
deGrasse Tyson took to Twitter to complain that the
latest Star Wars was using parsecs as units of time
instead of distance.
This Star Wars error is decades old - it was Han Solo's
gaffe in the original Star Wars - and I suspect J J
Abrams was deliberately trolling nerds by repeating it.
Technical dialogue in movies is often a series of
scientific words thrown together to quickly convey
something that feels technical. We need to invert the
neutrino quantum metric scanner, or some such nonsense.
That said, it's served its purpose. When Han Solo says
of the Millennium Falcon "It's the ship that made the
Kessell Run in less that 12 parsecs", the audience
knows he's bragging about his ship's speed.
Real technical discussion often takes far longer and
is far less accessible than movie dialogue. In the
minute following the real-life Apollo 13 explosion in
1970, the astronauts exchanged these words with
mission control:
Swigert: "Okay, Houston, we've had a problem
here."
Lousma: "This is Houston. Say again please."
Lovell: "Houston, we've had a problem. We've
had a main B bus undervolt."
Lousma: "Roger. Main B undervolt."
This surprisingly calm exchange doesn't convey the
lethal gravity of the situation.
The 1995 movie of Apollo 13 portrays these events
with a little more drama; the astronauts are not as
calm and time is compressed.
Actor Bill Paxton's line "We have a wicked shimmy up
here" was added to the movie dialogue, which is not
technical and further conveys to the audience that
something is really amiss.
A more common compromise in science fiction movies is
exposition. Mark Watney (played by Matt Damon) in The
Martian does a lot of thinking out loud that falls into
this category: "If I want water, I'll have to make it
from scratch. Fortunately, I know the recipe: Take
hydrogen. Add oxygen. Burn."
Would a real astronaut say this out loud? Perhaps not.
But is it scientifically accurate? Well, yes it is.
Are we willing to accept such compromises when
watching science fiction? I guess it depends on how
captivating the movie is and how pedantic we are.
I can suspend my scientific disbelief when watching
movies such as Star Wars: A New Hope. But don't get me
started on the midichlorians dialogue from the first
of the Star Wars prequels The Phantom Menace.
- Michael J Brown
Associate Professor at Monash University
* End of article *
shows / movies came up (e.g. Babblealong 5 vs Star Wars). By
coincidence this article was in yesterday's New Zealand herald
newspaper (23 January, 2016) ...
Be prepared to suspend scientific belief
when you go to the movies
----------------------------------------
It's a month since the release of Star Wars: The Force
Awakens, and for pedants there's much to find wrong with
the Star Wars movies. Laser beams moving slower than
300,000km a second, and that sort of thing.
To be honest, I can live with those inaccuracies. Star
Wars is a fantasy with spaceships instead of dragons,
and isn't supposed to be as scientifically accurate as,
say, The Martian or 2001: A Space Odyssey.
But could more science be slipped into science fiction,
including the Star Wars movies, without spoiling the
fun? Let's go off-world and see if it could happen.
Dogfights in outer space
A staple of science fiction is combat between spacecraft
flying through outer space. Unsurprisingly, these fights
of fancy are often reminiscent of combat on Earth.
In Star Wars, the spacecraft fly around like fighter
planes, with engines pushing them along the direction of
travel and with speeds that appear to be hundreds of
kilometres an hour.
But spacecraft orbiting just above our atmosphere travel
at almost 8km every single second (about 28,800km/h).
And because of the vacuum of space, they can orient
themselves arbitrarily.
If you want to slow your spaceship, just turn around,
"fly backwards" and fire your engines.
What would combat between two orbiting spacecraft be
like? Well, head-on two spaceships would approach each
other at almost 16km a second! Fast, but not exactly
cinematic.
If the combatants wanted to execute turns (and had
unlimited fuel), they would fire rockets at 90 degrees
to the direction of travel. It would be circle work in
outer space.
Executing a 180-degree turn would take some time at
these speeds. Even if you executed a crushing 10G turn,
it would take four minutes to turn around. Time enough
for a snack and some social media updates. Perhaps that
explains why movie directors prefer speeds and
manoeuvres barking back to the Battle of Britain.
Under pressure
The 1979 movie Alien (with Sigourney Weaver) was
famously advertised with the tagline "in space no one
can hear you scream.
Audible sound waves cannot travel through a vacuum, and
yet many science fiction movies feature sound effects in
the vacuum of space. This is particularly true for the
more fantastical movies, such as Star Wars and Star
Trek, whereas the more realistic ones tend to avoid this.
One thing that science fiction gets partially right is
explosive decompression. Atmosperic pressure is
101 kiloPascals or 14.7 pounds per square inch. Blow
open the hatch to your spacecraft and you'll briefly
have a big force pushing you out the door. But the power
of such forces is often grossly exaggerated.
In The Martian movie (spoiler alert), astronaut Mark
Watney is propelled with vast force from air leaking out
of a small hole in his space suit. If this was the way
air pressure worked, slicing your bike tyre open would
launch you metres into the air.
Fortunately, that doesn't happen.
If a kilogram of air was expelled from an astronaut's
space suit at 200km/h, an astronaut with a mass of 200kg
(that's including the space suit) would be accelerated
to just 1km/h.
Mark Watney wouldn't "get to fly around like Iron Man",
as he said in the movie, but would move closer to a
snail's pace.
Perhaps it is understandable that this is one of the
relatively few areas where The Martian sacrifices
scientific accuracy for drama.
Technobabble
It isn't hard to find errors in the technical dialogue
of science fiction movies. After the release of Star
Wars: The Force Awakens, American astrophysicist Neil
deGrasse Tyson took to Twitter to complain that the
latest Star Wars was using parsecs as units of time
instead of distance.
This Star Wars error is decades old - it was Han Solo's
gaffe in the original Star Wars - and I suspect J J
Abrams was deliberately trolling nerds by repeating it.
Technical dialogue in movies is often a series of
scientific words thrown together to quickly convey
something that feels technical. We need to invert the
neutrino quantum metric scanner, or some such nonsense.
That said, it's served its purpose. When Han Solo says
of the Millennium Falcon "It's the ship that made the
Kessell Run in less that 12 parsecs", the audience
knows he's bragging about his ship's speed.
Real technical discussion often takes far longer and
is far less accessible than movie dialogue. In the
minute following the real-life Apollo 13 explosion in
1970, the astronauts exchanged these words with
mission control:
Swigert: "Okay, Houston, we've had a problem
here."
Lousma: "This is Houston. Say again please."
Lovell: "Houston, we've had a problem. We've
had a main B bus undervolt."
Lousma: "Roger. Main B undervolt."
This surprisingly calm exchange doesn't convey the
lethal gravity of the situation.
The 1995 movie of Apollo 13 portrays these events
with a little more drama; the astronauts are not as
calm and time is compressed.
Actor Bill Paxton's line "We have a wicked shimmy up
here" was added to the movie dialogue, which is not
technical and further conveys to the audience that
something is really amiss.
A more common compromise in science fiction movies is
exposition. Mark Watney (played by Matt Damon) in The
Martian does a lot of thinking out loud that falls into
this category: "If I want water, I'll have to make it
from scratch. Fortunately, I know the recipe: Take
hydrogen. Add oxygen. Burn."
Would a real astronaut say this out loud? Perhaps not.
But is it scientifically accurate? Well, yes it is.
Are we willing to accept such compromises when
watching science fiction? I guess it depends on how
captivating the movie is and how pedantic we are.
I can suspend my scientific disbelief when watching
movies such as Star Wars: A New Hope. But don't get me
started on the midichlorians dialogue from the first
of the Star Wars prequels The Phantom Menace.
- Michael J Brown
Associate Professor at Monash University
* End of article *